CLUSTERING PROPERTIES OF BzK-SELECTED GALAXIES IN GOODS-N: ENVIRONMENTAL QUENCHING AND TRIGGERING OF STAR FORMATION AT z {approx} 2

Journal Article · Sat Sep 01 00:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/756/1/71· OSTI ID:22092438

Lihwai, Lin; Weihao, Wang; Yan, Chi-Hung ^[1]; Dickinson, Mark ^[2]; Jian, Hung-Yu ^[3]; Merson, A. I.; Baugh, C. M.; Helly, John; Lagos, Claudia del P ^[4]; Scott, Douglas; Meger, Nicole ^[5]; Foucaud, Sebastien ^[6]; Haojing, Yan ^[7]; Cheng, Yi-Wen ^[8]; Yicheng, Guo; Pope, Alexandra ^[9]; Kirsten, Franz ^[10]; Koo, David C. ^[11]; Messias, Hugo ^[12]; Simard, Luc ^[13] ; others, and

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1. Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 106, Taiwan (China)
2. National Optical Astronomy Observatory, 950 N. Cherry Ave., Tucson, AZ 85719 (United States)
3. Department of Physics, National Taiwan University, Taipei, Taiwan (China)
4. Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom)
5. Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada)
6. Department of Earth Sciences, National Taiwan Normal University, N Degree-Sign 88, Tingzhou Road, Sec. 4, Taipei 11677, Taiwan (China)
7. Center for Cosmology and AstroParticle Physics, The Ohio State University, 191 West Woodruff Avenue, Columbus, OH 43210 (United States)
8. Institute of Astronomy, National Central Universe, Jhongli, Taiwan (China)
9. Astronomy Department, University of Massachusetts, 710 N. Pleasant St., Amherst, MA 01003 (United States)
10. Argelander-Institut fuer Astronomie, University of Bonn (Germany)
11. UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
12. Centro de Astronomia e Astrofisica da Universidade de Lisboa, Observatorio Astronomico de Lisboa, Tapada da Ajuda, 1349-018 Lisboa (Portugal)
13. National Research Council of Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, British Columbia (Canada)

Using a sample of BzK-selected galaxies at z {approx} 2 identified from the CFHT/WIRCAM near-infrared survey of GOODS-North, we discuss the relation between star formation rate (SFR), specific star formation rate (SSFR), and stellar mass (M{sub *}), and the clustering of galaxies as a function of these parameters. For star-forming galaxies (sBzKs), the UV-based SFR, corrected for extinction, scales with the stellar mass as SFR{proportional_to}M{sup {alpha}}{sub *} with {alpha} = 0.74 {+-} 0.20 down to M{sub *} {approx} 10{sup 9} M{sub Sun }, indicating a weak dependence on the stellar mass of the SFR efficiency, namely, SSFR. We also measure the angular correlation function and hence infer the correlation length for sBzK galaxies as a function of M{sub *}, SFR, and SSFR, as well as K-band apparent magnitude. We show that passive galaxies (pBzKs) are more strongly clustered than sBzK galaxies at a given stellar mass, mirroring the color-density relation seen at lower redshifts. We also find that the correlation length of sBzK galaxies ranges from 4 to 20 h {sup -1} Mpc, being a strong function of M{sub K} , M{sub *}, and SFR. On the other hand, the clustering dependence on SSFR changes abruptly at 2 Multiplication-Sign 10{sup -9} yr{sup -1}, which is the typical value for 'main-sequence' star-forming galaxies at z {approx} 2. We show that the correlation length reaches a minimum at this characteristic value, and is larger for galaxies with both smaller and larger SSFRs; a dichotomy that is only marginally implied from the predictions of the semi-analytical models. Our results suggest that there are two types of environmental effects at work at z {approx} 2. Stronger clustering for relatively quiescent galaxies implies that the environment has started to play a role in quenching star formation. At the same time, stronger clustering for galaxies with elevated SSFRs ({sup s}tarbursts{sup )} might be attributed to an increased efficiency for galaxy interactions and mergers in dense environments.

• OSTI ID: 22092438
• Journal Information: Astrophysical Journal, Vol. 756, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ANGULAR CORRELATION
ASTRONOMY
ASTROPHYSICS
COLOR
COSMOLOGY
GALAXIES
GALAXY CLUSTERS
INFRARED SURVEYS
MAIN SEQUENCE STARS
MASS
NEAR INFRARED RADIATION
RED SHIFT
STAR EVOLUTION
UNIVERSE